Now showing items 1-3 of 3

    • Article

      Food selection of early grouper, Epinephelus coioides, larvae reared by the semi-intensive method 

      JD Toledo, SN Golez, M Doi & A Ohno - Suisan Zoshoku, 1997 - Japan Aquaculture Society
      The grouper, Epinephelus coioides, larvae were reared in outdoor tanks with nauplii of copepods and/or rotifers, Brachionus rotundiformis as food. Nauplii propagated in tanks consisted mainly of Pseudodiaptomus annandalei and Acartia tsuensis. Gut content was examined for a total of 953 larvae sampled from day 3 to day 10 (day of hatching being day 0) . Grouper larvae successfully started feeding on early stage nauplii even if their abundance was as low as ca. 100 ind./l and showed better survival and growth thereafter compared to those fed with rotifers only. Feeding incidence reached 100% on day 4 when nauplii were available and only on day 9 when rotifers were given alone. Selective feeding ability of larvae seemed to start from day 4 and the larvae thereafter preferred to feed on medium- and large-size nauplii than rotifers. Coastal calanoid copepods of the genera Pseudodiaptomus and Acartia could be reproduced in tanks and their nauplii can be used as food for marine fish larval rearing.
    • Article

      Preliminary studies on the rearing of the red-spotted grouper, Epinephelus coioides larvae using copepod nauplii as initial food. 

      JD Toledo, SN Golez, M Doi, RS Bravo & S Hara - UPV Journal of Natural Sciences, 1996 - University of the Philippines in the Visayas
      One day old red-spotted grouper (Epinephelus coioides) larvae from SEAFDEC, Iloilo, were packed at 3.300 ind/L and transported to Dagupan, Pangasinan for larval rearing. Transport time was about 10 hours. More than 90% of the larvae were active after transport. These were reared in two 7-on tanks (Tanks 1 and 2) using Acartia nauplii and rotifers as a initial food and in one 10-ton tank (Tank 3) provided with rotifers only. Feeding incidence at the onset of feeding (Day 3) was higher (90-95%) in Tanks 1 and 2 than in tank 3 (85%). All larvae sampled from days 4 – 10 in Tanks 1 and 2 had food in the gut while feeding incidence in Tank 3 was variable (75-100%). Larvae in Tanks 1 and 2 showed consistently higher food electivity for Acartia nauplii than rotifers. Higher survival rates were observed in Day 13 in tanks provided with copepod nauplii (16-18%) than with the rotifers only (2%). Average total length on Day 13 was higher in copepod-fed larvae (4.5 ± 0.5 mm) than larvae fed with rotifers only (3.0 ± 0.3mm). All larvae fed with rotifers alone died on Day 15. A total of 675 larvae were harvested on Day 45 from Tanks 1 and 2. These results indicate the feasibility of transporting one day old E. coioides larvae for at least 10 h and of using copepod nauplii as food for the first feeding E. coioides larvae.
    • Book chapter

      Transplantation, hatchery, and grow-out of window-pane oyster Placuna placenta in Guimaras and Iloilo 

      SS Garibay, SN Golez & AS Unggui - In T Bagarinao (Ed.), Research Output of the Fisheries Sector Program, 2007 - Bureau of Agricultural Research, Department of Agriculture
      The windowpane oyster Placuna placenta (local name kapis) used to be harvested in large quantities and support a shellcraft industry in the Philippines, particularly in Panay Island. But the fishery and the industry declined markedly by the 1990s. Studies were conducted to transplant kapis and also to develop hatchery techniques for it in an effort to counter the population depletion. Kapis with average shell heights of 7 cm and 10 cm were transplanted from Roxas City in northern Panay Island and from Oton, Iloilo in southern Panay to Taklong Island in Guimaras during the rainy season (July–November) and the dry season (February–June). Survival of the transplants was higher during the dry season (57–60%) than during the rains (35–48%). Sexually mature kapis 10 cm in shell height were induced to spawn by temperature manipulation, water level manipulation, and use of ultravioletirradiated sea water. Spawning was successfully induced by raising the water temperature to 29±0.5oC. Eggs measured 45 μm on average, and fecundity was 5,000–10,000 per female. Kapis larvae were reared on a combination of the microalgae Isochrysis galbana, Tetraselmis sp., and Chaetoceros calcitrans, maintained at a density of 100,000 cells/ml. Three water treatment schemes were tested for larval rearing: chlorination, ultraviolet irradiation, and filtration (control). Larvae survived to the umbo veliger stage (180 μm, day 10) in chlorinated sea water whereas mass mortality occurred at the straight-hinge stage (days 4–) in both UV-treated and filtered sea water.